Tonya is believed to be helping her son, the sheriff said on Monday, but authorities are not yet calling her a suspect in Couch's probation violation.

"Every lead is being investigated," Tarrant County Criminal District Attorney Sharen Wilson said.

Authorities say Ethan Couch's divorced father, Fred, is cooperating with investigators. He says he hasn't heard from Ethan or his ex-wife since his son failed to report to his probation officer.

Authorities released two photos of a black Ford pickup truck they say Ethan and his missing mother may be driving.

"We certainly believe they're together. We all have a strong suspicion and we believe that she's helping him and that she's assisting him," Tarrant County Sheriff Dee Anderson said in a press conference.

Cops say if Tonya couch is indeed helping her son evade the law, she will face criminal charges. Anderson said: “We're gonna prosecute her as fully as we can if she helps him at all.”

The U.S. Marshals service has issued a wanted poster offering $5,000 reward for information leading to Ethan Couch's capture.

The website of the local sheriff's department also lists 18-year-old Couch as "Most Wanted." The FBI is helping in the manhunt too.